On Mon, 4 Dec 2006, Claypole, David wrote: > THIS MESSAGE IS SUBJECT TO THE CONFIDENTIALITY NOTICE AT THE END OF THIS > COMMUNICATION > > > Thanks Louis > > I am using a windows client but only have uk.pool.ntp.org as a source, I > then sync my domain with this client. > > If I use ( net time /setsntp:"0.uk.pool.ntp.org 1.uk.pool.ntp.org > 2.uk.pool.ntp.org" ) does that mean it will check 3 servers before > adjusting ? I presume the 3 servers would have to be with a certain > threshold of each other before the Server changed its time. So if one > was 8 hours out then it wouldn't happen. > I have several ntpd server so let me try something to find out the answer to your question :
C:\Documents and Settings\HP_Administrator>net stop w32time C:\Documents and Settings\HP_Administrator>net time /setsntp:"192.168.11.11 192.168.11.9 192.168.11.8" C:\Documents and Settings\HP_Administrator>net start w32time Well, I think you might be safe with this setting because I now see the Windows XP machine connecting to all 3 ntpd servers everytime it polls for time. To be 100% sure, we would have to know what w32time does when one of the server has a huge 8 hours offset... It should obviously react properly. Let's just hope w32time doesn't do an average of the 3 results it gets... ;-))) Anyway you seems to be much safer with /setsntp:"0.uk.pool.ntp.org 1.uk.pool.ntp.org 2.uk.pool.ntp.org" so I would just leave it like that for now. If w32time is smart enough to handle bad servers, you should be fine. See Microsoft documentation at: http://technet2.microsoft.com/WindowsServer/en/library/71e76587-28f4-4272-a3d7-7f44ca50c0181033.mspx?mfr=true Don't forget to stop/start w32time although, I beleive it is needed for the new sntp configuration to be taken into account. > I quess the server I checked on Saturday @ 9:30 was out. > > Thanks > David Claypole > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Sent: 04 December 2006 13:54 > To: Claypole, David > Cc: [email protected] > Subject: Re: [time] 8 hour jump in time > > On Mon, 4 Dec 2006, Claypole, David wrote: > >> THIS MESSAGE IS SUBJECT TO THE CONFIDENTIALITY NOTICE AT THE END OF >> THIS COMMUNICATION >> >> >> Have been using the uk.pool.ntp.org service for some time now without >> any issues and its been great. On saturday at 09:30 our server sync'd > >> and jumped by 8 hours causing us a few issues. Just windering if >> anyone else had issues and if there is anything i can do to ensure it >> doesnt happen again. >> >> >> Thanks >> >> David Claypole >> >> > > Hi David, > > Are running ntpd ? If not I would recommend it. > > Basically, if you aren't running ntpd, you must be using some kind of > sntp client ( e.g. ntpdate on linux, w32time on windows). > > The sntp clients ( s is for simple) take their time from the first > available server as far as I can tell. This raise the risk of what > happend to you happening again. Any given server may go wrong (any clock > device also), not only servers from the pool. > > When you run ntpd you usually specify 3 or more time source servers to > connect to : > > 0.uk.pool.ntp.org > 1.uk.pool.ntp.org > 2.uk.pool.ntp.org > > ntpd is smart enough to detect if one of the 3 servers go wrong and ntpd > will continue to provide you with reliable time unless all servers go > wrong. > > If you do not run ntpd, consider setting at least 1 ntpd server for your > network and have your local machines read time from your own ntpd > server. > It is OK to use sntp client on your internal network because you can now > trust your own ntpd server to give the right time. > > If you are already running ntpd with multiple servers as source of time, > then something more serious did occur beacuse all the time source > servers would have to fail in order for an 8 hour glitch to occur. > > Louis > > > > > * * * * * * * * * * * * * * * * * * * * * * * * * * > This e-mail is private and may be confidential and is for the intended > recipient only. If misdirected, please notify us by telephone and confirm > that it has been deleted from your system and any copies destroyed. If you > are not the intended recipient you are strictly prohibited from using, > printing, copying, distributing or disseminating this e-mail or any > information contained in it. > * * * * * * * * * * * * * * * * * * * * * * * * * * > We use reasonable endeavours to virus scan all E-mails leaving the firm but > no warranty is given that this E-mail and any attachments are virus free. You > should undertake your own virus checking. The right to monitor E-mail > communications through our networks is reserved by us. > * * * * * * * * * * * * * * * * * * * * * * * * * * > > This message has been scanned for viruses by BlackSpider MailControl - > www.blackspider.com > Louis _______________________________________________ timekeepers mailing list [email protected] https://fortytwo.ch/mailman/cgi-bin/listinfo/timekeepers
